(NewsNation) — U.S. Rep. Liz Cheney, R-WY., suggested in a speech Wednesday night that the Jan. 6 investigative committee, which she co-chairs, might ask the Justice Department to pursue criminal charges against Trump allies who they say tried to tamper with witnesses.

Cheney, who has been widely ostracized by the Republican Party for her participation in the investigation against former President Donald Trump, called on fellow Republicans to choose between loyalty to Trump or the Constitution.

“Many others are urging that we not confront Donald Trump, that we look away,” Cheney said. “And that is certainly the easier path. One need only look at the threats that are facing the witnesses who’ve come before the Jan. 6 committee to understand the nature and the magnitude of that threat.”

On Tuesday, the committee heard testimony from Cassidy Hutchinson, a former aide to Trump’s Chief of Staff Mark Meadows, who described Trump as “irate” the day of the Capitol insurrection, painting the president as a man who had come unhinged as he beckoned for his security to take him to the Capitol.

Cheney said Hutchinson’s testimony presented Trump’s actions both during and leading up to the Capitol riot as “more chilling and more threatening” than first imagined. She also praised Hutchinson for her “bravery” in appearing before the committee, opening herself up to scorn from Trump and his allies.

“My fellow Americans, we stand at the edge of an abyss, and we must pull back,” Cheney said.

Pat Cipollone, a former lawyer in the Trump White House who is said to have pushed back against Trump’s scheme to overturn the 2020 presidential election, was subpoenaed by the committee Wednesday night.

Cipollone is of interest to the committee because he “repeatedly raised legal and other concerns about President Trump’s activities on January 6th and in the days that preceded,” it said in a statement. Cipollone is said to have called a letter making false election claims a “murder-suicide” pact

Cheney, the 55-year-old daughter of former Vice President Dick Cheney, meanwhile has to return to her home state and hit the campaign trail as she faces a tough primary against a Trump-backed challenger.

A Republican primary debate will be held in Wyoming pitting Cheney against the Trump-endorsed Harriet Hageman, among others, in what could be the biggest test yet of how far a Trump endorsement can go in the modern Republican Party.